Here's something I've found useful to folks learning the snake roll called the 'zigzag' cast. It's not an official cast but something I concocted as a concept cast to separate the timing of the cast from the circular motions that make it tricky. It's useful when a caster is a little confused by the "9" or the "e" or when the timing escapes during practice or learning.

Starting with the line tight downstream on the right bank w/ right hand up, pull the rod tip back (toward the rear) smoothly to "cock" the rod, then push the line straight forward toward the middle of the river forgetting about circles for a minute. When the line starts to loft forward, pull back against it into a d-loop before it has a chance to drop to the water. No 9's or e's in this, just back and forth to reveal the timing and forces at play.

If you are using anything but a really longbellied line, this back, forth, and back sequence should kick back a pretty good d-loop without using any circles or spirals. You will find that the longer you can make that forward 'nose', the more time (fractions of a second count) you will have to pull the d-loop out to the rear. Play around within that momentary balance of energy, gravity and time. Get comfortable with it, relaxed - focusing on the movement of the line rather shapes of the hands, arms, or rod tip.

Now do it again, but after cocking the rod back, go in an ever-so slightly overhand curved movement forward instead of pushing it straight ahead. You will notice that the curve puts much more energy into the 'nose' (loop thrown forward) and makes the pull back to the d-loop feel tight and smooth. It adds a third dimension, which makes it easier... but keep the same timing as you had in the zigs and the zags earlier.

Gradually increase the circular movement a bit at a time keeping the final shape oblong like a sausage (ref. snake roll originator Simon Gawesworth's mention in "Spey Casting" pg. 121) rather than circular until you find a really easy, surprisingly slow yet fully energized "groove" for the line to pass through.

You'll know it when you see it - the 'snake' loop suspends in mid air tightened by the dillema between the first push and the new pull.

The snake is really a great cast in every way - for casting and fishing, single or double hand. Although the "9" or "e" shapes help describe the path of the rod, sometimes the linear zigzag helps isolate the application of power and timing that can then be enhanced with circular movements.